Easton, which is owned by the same company as Bell and Giro, is giving you a free helmet from either brand, up to $250, when you buy an Easton wheelset.  The image at left (click to enlarge) lists the helmet credit you get for each set, which must be purchased through an authorized retailer.  Once you buy the wheels, the shop will give you a certificate that you send to Easton.  They’ll call you to recommend an appropriate helmet.  Upside: Free helmet and no rebate form to fill in.  Downside: They may try to upsell you and you don’t get your helmet immediately with purchase.
Click here for full promo details.